Armed with the millennial generation’s defining traits — Web savvy, boundless confidence and social networks that extend online and off — Stephen and his peers are forging a political identity all their own, often at odds with mainstream gay culture.

If the gay-rights movement today seems to revolve around same-sex marriage, this generation is seeking something more radical: an upending of gender roles beyond the binary of male/female. The core question isn’t whom they love, but who they are — that is, identity as distinct from sexual orientation.

But what to call this movement? Whereas “gay and lesbian” was once used to lump together various sexual minorities — and more recently “L.G.B.T.” to include bisexual and transgender — the new vanguard wants a broader, more inclusive abbreviation. “Youth today do not define themselves on the spectrum of L.G.B.T.,” said Shane Windmeyer, a founder of Campus Pride, a national student advocacy group based in Charlotte, N.C.

Part of the solution has been to add more letters, and in recent years the post-post-post-gay-rights banner has gotten significantly longer, some might say unwieldy. The emerging rubric is “L.G.B.T.Q.I.A.,” which stands for different things, depending on whom you ask…

“There’s a very different generation of people coming of age, with completely different conceptions of gender and sexuality,” said Jack Halberstam (formerly Judith), a transgender professor at the University of Southern California and the author, most recently, of “Gaga Feminism: Sex, Gender, and the End of Normal.”

“When you see terms like L.G.B.T.Q.I.A.,” Professor Halberstam added, “it’s because people are seeing all the things that fall out of the binary, and demanding that a name come into being.”

If history is any guide, the age gap won’t be so easy to overcome. As liberated gay men in the 1970s once baffled their pre-Stonewall forebears, the new gender outlaws, to borrow a phrase from the transgender writer Kate Bornstein, may soon be running ideological circles around their elders.

Still, the alphabet soup of L.G.B.T.Q.I.A. may be difficult to sustain. “In the next 10 or 20 years, the various categories heaped under the umbrella of L.G.B.T. will become quite quotidian,” Professor Halberstam said.

Even at the open mike, as students picked at potato chips and pineapple slices, the bounds of identity politics were spilling over and becoming blurry.

At one point, Santiago, a curly-haired freshman from Colombia, stood before the crowd. He and a friend had been pondering the limits of what he calls “L.G.B.T.Q. plus.”

“Why do only certain letters get to be in the full acronym?” he asked.